Strongly Anisotropic Quasi-1D BaTiS3 Chalcogenide Perovskite for Near-Infrared Polarized Photodetection

One-dimensional (1D) crystal-structural materials have attracted extensive attention for polarization detection because of the strong anisotropy. Barium titanium sulfide (BaTiS3), a quasi-1D chalcogenide perovskite, demonstrates a great potential for polarization detection stemming from the giant optical anisotropy. Whereas, the photoelectric properties of BaTiS3 and its direct application in polarized photodetector are less studied. Herein, quasi-1D BaTiS3 is introduced in polarized photodetection for the first time. The needle-like BaTiS3 single crystals are successfully prepared by a modified chemical vapor transport process. The BaTiS3 single crystal demonstrates a narrow bandgap of 0.8 eV, an n-type intrinsic conductivity, and a more than 300 cm(2) V-1 s(-1) mobility along the c-axis. Then, an Ag/BaTiS3/Ag photoconductive detector is fabricated. It shows a broad detection wavelength ranging from visual light to 1550 nm and high responsivity of approximate to 1.22 A W-1. Moreover, an orthogonal reverse property of polarization photocurrent is observed under the excitation energy of 1.70 eV and 1.96 eV. These comprehensive characteristics can promote the application of the quasi-1D BaTiS3 in near-infrared polarized photodetection.

Automated summary

In this study, quasi-1D BaTiS3 was introduced for polarized photodetection, and needle-like BaTiS3 single crystals were successfully prepared. The single crystal exhibits a narrow bandgap, n-type conductivity, and high mobility, enabling high responsivity polarized photodetection over a wide wavelength range.